/*
 * sftp.h: definitions for SFTP and the sftp.c routines.
 */

#include "int64.h"

#define SSH_FXP_INIT 1             /* 0x1 */
#define SSH_FXP_VERSION 2          /* 0x2 */
#define SSH_FXP_OPEN 3             /* 0x3 */
#define SSH_FXP_CLOSE 4            /* 0x4 */
#define SSH_FXP_READ 5             /* 0x5 */
#define SSH_FXP_WRITE 6            /* 0x6 */
#define SSH_FXP_LSTAT 7            /* 0x7 */
#define SSH_FXP_FSTAT 8            /* 0x8 */
#define SSH_FXP_SETSTAT 9          /* 0x9 */
#define SSH_FXP_FSETSTAT 10        /* 0xa */
#define SSH_FXP_OPENDIR 11         /* 0xb */
#define SSH_FXP_READDIR 12         /* 0xc */
#define SSH_FXP_REMOVE 13          /* 0xd */
#define SSH_FXP_MKDIR 14           /* 0xe */
#define SSH_FXP_RMDIR 15           /* 0xf */
#define SSH_FXP_REALPATH 16        /* 0x10 */
#define SSH_FXP_STAT 17            /* 0x11 */
#define SSH_FXP_RENAME 18          /* 0x12 */
#define SSH_FXP_STATUS 101         /* 0x65 */
#define SSH_FXP_HANDLE 102         /* 0x66 */
#define SSH_FXP_DATA 103           /* 0x67 */
#define SSH_FXP_NAME 104           /* 0x68 */
#define SSH_FXP_ATTRS 105          /* 0x69 */
#define SSH_FXP_EXTENDED 200       /* 0xc8 */
#define SSH_FXP_EXTENDED_REPLY 201 /* 0xc9 */

#define SSH_FX_OK 0
#define SSH_FX_EOF 1
#define SSH_FX_NO_SUCH_FILE 2
#define SSH_FX_PERMISSION_DENIED 3
#define SSH_FX_FAILURE 4
#define SSH_FX_BAD_MESSAGE 5
#define SSH_FX_NO_CONNECTION 6
#define SSH_FX_CONNECTION_LOST 7
#define SSH_FX_OP_UNSUPPORTED 8

#define SSH_FILEXFER_ATTR_SIZE 0x00000001
#define SSH_FILEXFER_ATTR_UIDGID 0x00000002
#define SSH_FILEXFER_ATTR_PERMISSIONS 0x00000004
#define SSH_FILEXFER_ATTR_ACMODTIME 0x00000008
#define SSH_FILEXFER_ATTR_EXTENDED 0x80000000

#define SSH_FXF_READ 0x00000001
#define SSH_FXF_WRITE 0x00000002
#define SSH_FXF_APPEND 0x00000004
#define SSH_FXF_CREAT 0x00000008
#define SSH_FXF_TRUNC 0x00000010
#define SSH_FXF_EXCL 0x00000020

#define SFTP_PROTO_VERSION 3

/*
 * External references. The sftp client module sftp.c expects to be
 * able to get at these functions.
 *
 * sftp_recvdata must never return less than len. It either blocks
 * until len is available, or it returns failure.
 *
 * Both functions return 1 on success, 0 on failure.
 *
 * sftp_sendbuffer returns the size of the backlog of data in the
 * transmit queue.
 */
int sftp_senddata(char *data, int len);
int sftp_sendbuffer(void);
int sftp_recvdata(char *data, int len);

/*
 * Free sftp_requests
 */
void sftp_cleanup_request(void);

struct fxp_attrs {
  unsigned long flags;
  uint64 size;
  unsigned long uid;
  unsigned long gid;
  unsigned long permissions;
  unsigned long atime;
  unsigned long mtime;
};

/*
 * Copy between the possibly-unused permissions field in an fxp_attrs
 * and a possibly-negative integer containing the same permissions.
 */
#define PUT_PERMISSIONS(attrs, perms)                                          \
  ((perms) >= 0 ? ((attrs).flags |= SSH_FILEXFER_ATTR_PERMISSIONS,             \
                   (attrs).permissions = (perms))                              \
                : ((attrs).flags &= ~SSH_FILEXFER_ATTR_PERMISSIONS))
#define GET_PERMISSIONS(attrs)                                                 \
  ((attrs).flags & SSH_FILEXFER_ATTR_PERMISSIONS ? (attrs).permissions : -1)

struct fxp_handle {
  char *hstring;
  int hlen;
};

struct fxp_name {
  char *filename, *longname;
  struct fxp_attrs attrs;
};

struct fxp_names {
  int nnames;
  struct fxp_name *names;
};

struct sftp_request;
struct sftp_packet;

const char *fxp_error(void);
int fxp_error_type(void);

/*
 * Perform exchange of init/version packets. Return 0 on failure.
 */
int fxp_init(void);

/*
 * Canonify a pathname. Concatenate the two given path elements
 * with a separating slash, unless the second is NULL.
 */
struct sftp_request *fxp_realpath_send(const char *path);
char *fxp_realpath_recv(struct sftp_packet *pktin, struct sftp_request *req);

/*
 * Open a file. 'attrs' contains attributes to be applied to the file
 * if it's being created.
 */
struct sftp_request *fxp_open_send(const char *path,
                                   int type,
                                   struct fxp_attrs *attrs);
struct fxp_handle *fxp_open_recv(struct sftp_packet *pktin,
                                 struct sftp_request *req);

/*
 * Open a directory.
 */
struct sftp_request *fxp_opendir_send(const char *path);
struct fxp_handle *fxp_opendir_recv(struct sftp_packet *pktin,
                                    struct sftp_request *req);

/*
 * Close a file/dir. Returns 1 on success, 0 on error.
 */
struct sftp_request *fxp_close_send(struct fxp_handle *handle);
int fxp_close_recv(struct sftp_packet *pktin, struct sftp_request *req);

/*
 * Make a directory.
 */
struct sftp_request *fxp_mkdir_send(const char *path);
int fxp_mkdir_recv(struct sftp_packet *pktin, struct sftp_request *req);

/*
 * Remove a directory.
 */
struct sftp_request *fxp_rmdir_send(const char *path);
int fxp_rmdir_recv(struct sftp_packet *pktin, struct sftp_request *req);

/*
 * Remove a file.
 */
struct sftp_request *fxp_remove_send(const char *fname);
int fxp_remove_recv(struct sftp_packet *pktin, struct sftp_request *req);

/*
 * Rename a file.
 */
struct sftp_request *fxp_rename_send(const char *srcfname,
                                     const char *dstfname);
int fxp_rename_recv(struct sftp_packet *pktin, struct sftp_request *req);

/*
 * Return file attributes.
 */
struct sftp_request *fxp_stat_send(const char *fname);
int fxp_stat_recv(struct sftp_packet *pktin,
                  struct sftp_request *req,
                  struct fxp_attrs *attrs);
struct sftp_request *fxp_fstat_send(struct fxp_handle *handle);
int fxp_fstat_recv(struct sftp_packet *pktin,
                   struct sftp_request *req,
                   struct fxp_attrs *attrs);

/*
 * Set file attributes.
 */
struct sftp_request *fxp_setstat_send(const char *fname,
                                      struct fxp_attrs attrs);
int fxp_setstat_recv(struct sftp_packet *pktin, struct sftp_request *req);
struct sftp_request *fxp_fsetstat_send(struct fxp_handle *handle,
                                       struct fxp_attrs attrs);
int fxp_fsetstat_recv(struct sftp_packet *pktin, struct sftp_request *req);

/*
 * Read from a file.
 */
struct sftp_request *fxp_read_send(struct fxp_handle *handle,
                                   uint64 offset,
                                   int len);
int fxp_read_recv(struct sftp_packet *pktin,
                  struct sftp_request *req,
                  char *buffer,
                  int len);

/*
 * Write to a file. Returns 0 on error, 1 on OK.
 */
struct sftp_request *fxp_write_send(struct fxp_handle *handle,
                                    char *buffer,
                                    uint64 offset,
                                    int len);
int fxp_write_recv(struct sftp_packet *pktin, struct sftp_request *req);

/*
 * Read from a directory.
 */
struct sftp_request *fxp_readdir_send(struct fxp_handle *handle);
struct fxp_names *fxp_readdir_recv(struct sftp_packet *pktin,
                                   struct sftp_request *req);

/*
 * Free up an fxp_names structure.
 */
void fxp_free_names(struct fxp_names *names);

/*
 * Duplicate and free fxp_name structures.
 */
struct fxp_name *fxp_dup_name(struct fxp_name *name);
void fxp_free_name(struct fxp_name *name);

/*
 * Store user data in an sftp_request structure.
 */
void *fxp_get_userdata(struct sftp_request *req);
void fxp_set_userdata(struct sftp_request *req, void *data);

/*
 * These functions might well be temporary placeholders to be
 * replaced with more useful similar functions later. They form the
 * main dispatch loop for processing incoming SFTP responses.
 */
void sftp_register(struct sftp_request *req);
struct sftp_request *sftp_find_request(struct sftp_packet *pktin);
struct sftp_packet *sftp_recv(void);

/*
 * A wrapper to go round fxp_read_* and fxp_write_*, which manages
 * the queueing of multiple read/write requests.
 */

struct fxp_xfer;

struct fxp_xfer *xfer_download_init(struct fxp_handle *fh, uint64 offset);
void xfer_download_queue(struct fxp_xfer *xfer);
int xfer_download_gotpkt(struct fxp_xfer *xfer, struct sftp_packet *pktin);
int xfer_download_data(struct fxp_xfer *xfer, void **buf, int *len);

struct fxp_xfer *xfer_upload_init(struct fxp_handle *fh, uint64 offset);
int xfer_upload_ready(struct fxp_xfer *xfer);
void xfer_upload_data(struct fxp_xfer *xfer, char *buffer, int len);
int xfer_upload_gotpkt(struct fxp_xfer *xfer, struct sftp_packet *pktin);

int xfer_done(struct fxp_xfer *xfer);
void xfer_set_error(struct fxp_xfer *xfer);
void xfer_cleanup(struct fxp_xfer *xfer);
